Water-proofing of concrete or masonry surfaces



March 18, 1958 J. G. AFFLECK 2,827,397

WATER-PROOFING OF CONCRETE OR MASONRY SURFACES Filed Aug. 25, 1954 IMPERMEABLE NONPEPTIZABLE COATING* GROUND LINE FIG.3 v

CINDER BLOCKS WALL m SECTION GINDER BLOCK '3 h IMPERMEABLE NONPEPTIZABLE GOATING* IMPERMEABLE NONPEPTIZABL F|G.6 COATING IMPERMEABLE NONPEPTIZABLE F |(5 4 COATING*\ GONGRETEYTANK FIG.5

. I5 BR'GK BRICK BUlLDlNG *AQUEOUS COMONOMER SOLUTION OF MONOFUNGTIONAL AND POLYFUNCTIONAL OUTER ACRYLIC COMPOUNDS WALL POLYMERIZED TO GEL SURFACE STAGE m SITU INVENTOR.

JAMES e. AFFLEGK BY IMPERMEABLE f NONPEPTIZABLE GOATING* ATTORNEY United States WATER-PROOFING OF CONCRETE OR MASONRY SURFACES James G. Aflleck, Darlen, Conn.,' assignor to American Cyanamid Company, New York, N. Y., a corporation of Maine Application August 23, 1954, Serial No. 451,680

14 Claims. (Cl. 117-123) prepared for application to the interior side of subsoil masonry walls which reduces or eliminates the penetration of moisture to a satisfactory degree.

An object of the invention is to provide an improved preformed masonry structure.

Another object of the invention is to provide a method reat 'i for rendering porous masonry substantially impermeable to liquids.

A further object of. the invention is to provide an improved structure which is substantially impervious to the penetration of liquids.

I Still another object of the invention is to provide an economical method for water-proofing masonry walls from the interior of the masonry structure.

Other objects and benefits of the invention will be apparent to those skilled in the art from the detailed description hereinbelow.

The above and other objects of the invention may be accomplished by the treatment of porous masonry, either laid in situ or preformed, including concrete, brick, stone, clay, tile, cinder blocks, mortar and other masonry joint materials, with a solution containing a monofunctional acrylic compound and a polyfunctional monomeric acrylic compound. The invention accordingly comprises a process of impregnating rigid preformed porous masonry with a solution comprising a monofunctional monomer having a single radical of the group consisting of acrylyl and methyacrylyl radicals as a major portion of the solute and a polyfunctional monomer having two or more of the same radicals as a minor portion of the solute followed by polymerizing the monomeric material in situ to a water-impermeable nonpeptizable gel and also the resulting treated masonry structure.

Suitable monofunctional acrylic compounds for use in the present invention include acrylamide, N-methylol acrylamide, acrylic acid, hydroxyethyl acrylate and the water-soluble monovalent salts of acrylic acid as exemplified by ammonium acrylate, sodium acrylate, potassium acrylate, and also by the monoamine salts of acrylic acid as exemplified by the methylamine, ethylamine and propylamine salts of the acid, as well as mixtures of any of the aforesaid substances. The corresponding methacrylic compounds are equally operative as is any other monomer containing a single acrylyl or methacrylyl radical which is substantially soluble in water, that is to the extent of at least about 3%, in order to permit its application in the desired aqueous solution. Acrylamide is the preferred monofunctional compound since it produces excellent results and is relatively low in price.

The polyfunctional comonomer employed in the instant treatment of masonry is one containing two or more acrylyl or methacrylyl groups per molecule. Alkylidene diacrylamides or alkylidene dimethacrylamides of the type disclosed in Lundberg Patent 2,475,846 are preferred for the purpose provided that they are at least sparingly soluble in Water, for instance to the extent of 0.25% by weight or more. This group of compounds is best illustrated by reference to the following general formula:

0 R" It in which R'CH is the hydrocarbon residue of an aldehyde and R and R are either methyl or hydrogen.

The RCH in the above formula may be the hydrocarbon residue of formaldehyde, acetaldehyde, propionaldehyde, butrylaldehyde, pentanal, crotonaldehyde, benzaldehyde, furfural, salicylaldehyde, cinnamic aldehyde, or the like. In other words, R may be hydrogen, alkyl, alkenyl, aralkyl, aralkenyl, aryl or heterocyclic. Instead of formaldehyde itself, paraformaldehyde such as hexamethylenetetramine may be used to produce the most useful resin intermediates which are methylene bis-acrylamides.

Methylene bis-acrylamide is preferred for the purpose since it is an excellent cross-linking agent for acrylamide and other similar monofunctional compounds in the copolymerization reactions with which the present invention is concerned. However, other polyfunctional acrylyl or methacrylyl monomers of mixtures thereof may also be employed including 1,3-diacrylyl-1,3,5-hexahydrotriazine, -1,3,5-triacrylyl-1,3,5-hexahydrotriazine and the corresponding methacrylic acid derivatives, as well as the salts containing two or more acid radicals of acrylic or methacrylic acid with bivalent or other polyvalent metals as exemplified by beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, copper, mercury, manganese, chromium, molybdenum, nickel, antimony, zirconium, etc., as well as the diacrylate or dimethacrylate of ethylene glycol. The preparation of these monomers is known to those skilled in the an and accordingly is not set forth herein.

The proportions of monofunctional and polyfunctional monomers are critical and the latter should range from about 0.5% to 25% and preferably between 3 and 10% of the total weight of polymerizable material. These proportions are essential in order to produce a gel polymer of the desired characteristics, that is, one which is compatible with water in the sense that a dried gel will be reactivated or swollen again by water and yet one which is impermeable to the passage through the swollen gel of any sub stantial quantities of water or moisture. If the amount of cross-linking between the linear chains derived from the monofunctional monomer is too small, the polymer is of an essentially linear or water-soluble nature and such polymers may be leached out of the masonry by the action of water or moisture. On the other hand too high a degree of cross-linking in the resulting resin will destroy its gel characteristics and tend to convert it to a rigid threedimensional resin which will not swell upon rewetting. Accordingly the polyfunctional component must always be present in minor quantities relative to the monofunctional monomer.

Polymerization of the vinylgroups of the compounds used in this invention is effected with any of the usual I water-soluble oxygen-containing catalysts, such as tertiary butyl hydroperoxide, the ammonium, potassium and sodium persulfates, hydrogen peroxide, the alkali metaland ammonium chlorates, perborate's, percarbonates, and the like. It is frequently advantageous to use a redox catalyst system. of oxygen-containing compound with a reducing agent, such as sodium 'thiosulfate, sodiumor potassium bisulfite, hydroquinone, tetc., a typical ,cornbination'being ammonium persulfate andsodium thiosulfate. The quantity of catalyst used is not considered criticaland, in general, from.about"O.1-% toabout based onthe weight of polymerizable monomers may be used;

The rate ofgel formation of aparticular resin may vary depending .upon whetherlpolymerization is. effected in the presence of acid or,alkali,land this ,.factor .,Shouldalso be considered in determining f the polymerizationconditions.

The rate of copolymerization or gel formation varies directly with bothtemperatur-eand concentration of the initiator or catalyst, and the 'timeof gelatio'n may vary cinder blocks, or concrete, and for eliminating the seepage of water and other liquids from concrete tanks.

Inpracticing the present process, the total concentration of monomers in the solution may range from about'3 to about 50% or more depending on the solubilities of the particular comonomers and the acceptability of the extra expense of an extremely heavy treatment. Concentrations ofiabout 3 .to 20% are preferable for most purposes and especially good-results are-obtainable with solutions containing about l0 ofthecomonomers The quantity of themonomerlcagents employed will, of course, vary with the porosity of the masonryundergoing treatmentand the desired depthof impregnation.

from a few minutes to 8 hours. or more. In the treatment of masonry, it is often impractical to adjust the temperature; therefore, the polymerization rate is usually controlled .by selection .of. the optimum catalyst: monomer ratio. However, the TgeIation time, isusually 'of little in:- portance-and is best determined and adjusted byexperiments on the .actual site of operationsusing varyingratios of catalyst .to the comonomers. ltfshould ,ofcourse be sufiicientlyllong to permit mixing sizable batches of the monomers and .cataly ston the job and application thereof to masonry surfaces without premature gelling. V

In gene rahlsolutions used in the instantprocess have excellent wetting characteristicsand will require no wetting. agent .to aid their penetrating deeply enough into the pores of masonry. However, where an extremely heavy treatment is required forsome special purpose, it is contemplatedthat asuitable wetting agent such as di-Z-ethylhexyl ester .offsodium' sulfosuccinate or other a compatible wetting agentmay be employed. In some instances it may be necessary to:add a compatible thickening agentfor economy in preventing too deep a penetration into the porous structural material. Suitable thickener-s include casein, glues, gelatin, gums, and carboxymethyl cellulose. It is toqbe emphasized, however, that the present treatment does not amount to amere coating of the surface, for the copolymeric gels'described herein readily rub or wear off of the vsurfaces and therefore cannot provide the effect which isdesired; The monomeric solution must penetrate into the pores 'of the masonryand also into any ,small cracks ortcreyices which mightpermit the passage of water.

In general, it appears desirable :to impregnate the masonry to a depth of ;at least about A inch and the maximum depth of impregnation appears to be limited only by economic considerations. The total quantity of monomeric agents applied may vary from about 0.005 up to about 055 pound per squarefoot of masonrybeing treated and even up to 3 or more pounds per square foot for special purposes in which the added cost is The present treatment appears to be capable of withstanding comparatively high water pressures inasmuch as there seems to' be no tendency for the gel to peel otf or otherwise to'be displaced from the interior of pores of the sizetencountered in various types of masonry. Large crevices in the masonry ,s'hould'betfilled with mortar in the usual fashion of making such repairs, but the novel treatment provides an adequate seal for smaller cracks. For abetter understanding of the nature and objects of the invention, reference should be had to the follow- 7 ing examples which are intended to illustrate the inven- The orestadiacent the vsinfaceto be treated should b thorough y imp gnated or filled with the solution. of comonomers which then polymerizes in situ into .gQl fQrm. In general, it appears that ;ornpara ively little :is to be ained by impregnatingth mason y-to a considerable depth and .s ch tr a men re ofco rsernore cost y- The solutions described herein may bez pplied in any s itable manner, for example .by spraying, brushing, .or floodingthe solution ontothe masonry to the treated. In d t on, it appears immaterial whether theimpregnant is applied to the exterior;0r interior walls ofthe preformed masonry structure, as'the treatments operate by forming a gel inside the poreswhichis. compatible with water. but impermeable to it. Water seepagethroughthe.masonry is checked either by the swollen .gelorby thereactivation ofa gel which has dried'in the pores. T hisrewetting effect .is comparatively rapid so the-seepage swells the dried gel back to its original state and hence'blocks the passage of any appreciable amount of water. Interior application of the treatment is a major advantage of the present proc ess since itis usually far easier to apply theimpregnant in this manner, inasmuchas it may "be used in 'finishedbasements or cellars without requiring'the excavation of earth from the exterior walls. However, the invention is not limited to the'treatmentof cellars and other underground masonry, as it is equally effective in preventingtheseepe age of wind-driven rainthrough building .Walls of'brick,

tion and which allportions are given in terms of weight 7 7 unless otherwise specified.

Example I Y 7 'Parts by weight Acrylamide 95 N,N-methylene bis-acrylamide 5' Tertiary butylhydroperoxide 6 Water 894 The above monomers are dissolved in the water with stirring and .theperoxide catalyst is. added immediately before .application to brick andto the cinder block structure mentioned below. p

A common ,unglazed smooth building brick is sprayed on all surfaces with the abovesolution and then allowed toQStandior .6 hours to insure complete polymerization. Ihegtreatedbrick, along withasimilar untreated brick, is firstweighed ahdthenimmersed in 'a in a vessel containing waterat room temperature for a period of one hour. Next,',both' bricks areremoved from the water, rubbed dry. with (cloths. to remove surface moisture and then .reweighed. The weightof the untreated brick is found .to be. substantially .greater due to the absorption of waterinto its interiontwhereas the treated brick displays only .a negligible weight increase as a result of the immersion. r

A hollow column is erected on a concrete slab to a height of approximately '50 inches by laying 6 hollow commercial 8."-x..8." ,x 1.6" cinder blocks containing a center web upon one another. A conventional building mortar is used tosealthe joints between the blocks and the..mortarisl.allowed to cure. thoroughly for 30 days. Ihisstructure.containsl vertical'wells or tubes and the solution ,des'cribedab'ove ispoured .into one of these and thensyphonedvofirinlsuch a manner thatthetreating agent isinicontact with .the inasonry for :an average of about 30 minutes; The" bottom of the treated well is dried with wadding attached to a handle of suflicient length and'l'allowed to r'emain empty overnight. Next, both wells .Iare filled to :a depthof -4 feet with .water at room temperature. After 124 hours itis observed that the'sur- Example 11 Parts by weight N-methylol acrylamide 97 1,3,5-triacrylyl 1,3,5-hexal1ydrotriazine 3 Tertiary butyl hydroperoxide 6 Water 1894 Example I is repeated using the above treating solution on fresh test specimens and similar results are obtained.

Example Ill Parts by weight Methacrylamide 95 Calcium acrylate Tertiary butyl hydroxide 6 Water 394 The tests described in Example-I are repeated with a solution of this composition and again it is apparent that a very high degree of water-proofing is obtained with the unglazed brick and with the cinder block and mortar column.

Example IV Parts by weight Sodium acrylate 95 Ethylene glycol dimethacrylate 5 Tertiary butyl hydroperoxide 6 Water 894 Treating and testing another cinder block well and brick according to the procedure of Example I with the above solution, it is again evident that both the brick and the cinder block well are rendered impermeable to water.

The tests are again repeated with fresh masonry using the aqueous agent described above and again no significant increase in the weight of the treated brick or exudation of moisture onto the exterior surface of the cinder blocks surrounding the treated well are noted.

In the drawings:

Fig. l is a cross-sectional portion of a preformed masonry basement foundation with the polymer gel coating of the invention applied to the interior wall and floor.

Fig. 2 and Fig. 5 show a cinder block and building brick respectively in cross section with the coating applied to the surfaces.

Fig. 3 shows the coating applied to the inner well surfaces of a preformed cinder block wall.

Fig. 4 shows a concrete tank which has been coated at the outer surface by the polymer gel.

Fig. 6 shows a brick wall in cross section with the outer surface coated with the polymer gel of the invention.

In a more detailed description of the figures of the drawing, Fig. 1 shows the polymer gel coating 8 applied to the inner wall and floor of a building basement foundation 9 which is supported by and contacted at its outer adjacent surfaces by earth 10. The foundation wall 9 as shown is poured concrete, although the coating may also be applied to other preformed basement masonry founda tion construction, such as cinder block.

Fig. 2 shows a cinder block 11 which has the water impermeable coating 12 of the invention applied to the inner well surfaces and to the outer surfaces and Fig. 5 shows the coating 18 applied to an unglazed building brick 17.

The treatment of building walls of preformed masonry is illustrated by the embodiments of Fig. 3 and Fig. 6. In Fig. 3 the coating 14 of the invention is shown applied to the inner vertical well walls formed by cinder blocks 13" and in Fig. 6 the building wall formed of bricks 19 isv shown with the water impermeable coating 20 applied to the outer surface of the wall.

In Fig. 4, the water impermeable polymer gel coating 16 of the invention is shown applied to the outer surface of the concrete tank wall 15.

While there are above disclosed but a limited number of embodiments of the process and treated article of the invention herein presented, it is possible to produce still other embodiments without departing from the inventive concept herein disclosed, and it is desired therefore that only such limitations be imposed on the appended claims as are stated therein or required by the prior art.

I claim:

1. An article which comprises porous masonry having pores containing a gel formed by the copolymerization of a major portion of monofunctional monomer having a single radical of the group consisting of acrylyl and methacrylyl radicals and a solubility in water of at least 3% by weight with between about 0.5 and about 25 percent by weight based on the total polymerizable matter of a polyfunctional monomer having at least two radicals of the group consisting of acrylyl and methacrylyl radicals and having a solubility in water of at least 0.25% by weight.

2. An article which comprises a preformed porous rigid masonry structure having pores containing a waterimpermeable nonpeptizable gel formed in situ by the copolymerization of a major portion of a water-soluble monofunctional monomer having a single radical of the group consisting of acrylyl and methacrylyl radicals with between about 0.5 and about 25 percent by weight based on the total polymerizable matter of a water-soluble polyfunctional monomer having at least two radicals of the group consisting of acrylyl and methacrylyl radicals.

3. An article according to claim 2 in which the polyfunctional monomer comprises an alkylidene diacrylamide.

4. An article according to claim 2 in which the polyfunctional monomer comprises methylene bis-acrylamide.

5. An article according to claim 2 in which the copolymeric gel is formed by the polymerization of monomers comprising acrylamide and methylene bisacrylamide.

6. An article according to claim 2 in which the copolymeric gel is formed by the polymerization of monomers comprising N-methylol acrylamide and methylene bis-acrylamide.

7. An article resistant to penetration by moisture which comprises a preformed porous rigid masonry structure having pores adjacent the surface containing at least about 0.005 pound on a dry basis per square foot of masonry surface of a water-impermeable nonpeptizable gel formed in situ by the copolymerization of a major portion of acrylamide with between about 0.5 and about 25 percent by weight based on the total polymerizable matter of methylene bis-acrylamide.

8. A process which comprises impregnating porous masonry with a solution comprising a monofunctional monomer having a single radical of the group consisting of acrylyl and methacrylyl radicals as a major portion of the solute and between about 0.5 and about 25 percent by weight based on the total polymerizable material of a polyfunctional monomer having at least two radicals of the group consisting of acrylyl and methacrylyl radicals as a minor portion of the solute, and copolymerizing the monomeric material in situ to a water-impermeable gel to seal the masonry against substantial penetration by moisture.

9. A process which comprises impregnating the pores of a preformed porous rigid masonry structure with an aqueous solution of a major portion of a water-soluble monofunctional monomer having a single radical of the group consisting of acrylyl and methacrylyl radicals and between about 0.5 and 25 percent by weight based on V we bis=ac ylamidethe total pelymerizablez matenialbfii a water-soluble, poly: func'ti'onabmonomen haviiiga at; least; twmradical's of the; givoixpaconsis ing: of: acxiyly]; and; methecrylyl radicals; and; copolymerizing the monomeric in tsitus to; a;

11. A process according to claim 9 i1; which theapolyfunctional monomer comprises methylene bis -acrylamide.

1 2'. A prowess according to claim-9 it which said? monomer comprise acr ylamide and methylene biwtcr-yk amide' '7 1.3. A process according'to c1aimf 9 in whieb said monomers comprise N metfiy1eI-,-acry1amicfeend methyl- 14. A grocess hi'ciicompfises-inipregnatihg poi'es ad'- iacent the surface of agreformec porous rigi'd masonry structute with' at least about OlOO'S pound ofisolute per sqpare fogtg 0i the rbesonry suriacein 'an aqueous solu.-.

tion, comgxfisinggbetween about 3 iandebout, 50=percent by weight .o i ;a. solu tm ckontgiping e majpr portioiiuoii acrylamide and between about 0.5 and about 25partsby weight of methylene bis-acrylami'de per 100 parts of total 7 poiymerizabiemetter, and copolymer izing the monomeric mate'riab in "situ to a water-impermeable nonpegtizabie gel to 'seai-the'masonry' ageinstsubst'antial penetration bymoisture;--"

U. S. DEPARTMENT OF COMMERCE PATENT OFFICE CERTIFICATE GE is Patent No, 2,827,397

March 18;, 1958 James Go Affleck It is hereby certified that error of the above numbered patent requiring appears in the, printed specification Patent should read as corrected below.

correction and that the said Letters Column 4, line 51, strike out "in a",

first occurrence; line 61 after "radicals' insert and a so column 6 3% by weight==g lubility in Water of at least line 65, after "radicals" insert =-=ar1d having a solubility in. Water of at least 025% by Weight-a Signed and sealed this 20th day of May 1958 Attest:

KARL HO AXLINE ROBERT Ca WATSON Attesting Officer of Patents 

1. AN ARTICLE WHICH COMPRISES POROUS MASONRY HAVING PORES CONTAINING A GEL FORMED BY THE COPOLYMERIZATION OF A MAJOR PORTION OF MONOFUNCTIONAL MONOMER HAVING A SINGLE RADICAL OF THE GROUP CONSISTING OF ACRYLYL AND METHACRYLYL RADICALS AND A SOLUBILITY IN WATER OF AT LEAST 3% BY WEIGHT WITH BETWEEN ABOUT 0.5 AND ABOUT 25 PERCENT BY WEIGHT BASED ON THE TOTAL POLYMERIZABLE MATTER OF A POLYFUNCTIONAL MONOMER HAVING AT LEAST TWO RADICALS OF THE GROUP CONSISTING OF ACRYLYL AND METHACRYLYL RADICALS AND HAVING A SOLUBILITY IN WATER OF AT LEAST 0.25% BY WEIGHT. 